Found the T/S Parameters. Can someone define these for me Qes,Qts,Cms, Sen db never understood that, and Le mH !

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Qes and Qts are refering to the driver's self damping. This refers to how well the driver controls itself at resonance, fs. An underdamped system will sound sloppy, because there is not enough restoring force on the system. Qes is refering to damping provided by the motor, only regarding the electrical losses, Qms is regarding the damping provided by the suspension, such as the surround and spider, and Qts is just the total driver damping. A high peak at resonance means the driver has excellent control over itself and won't ring for long, considering a free air environment (when the box comes into play, many variables need to be considered). So a cheap crappy woofer will usually have a not so big peak at its resonance, meaning the resitance to change is not so great, so it can easily ring. One with a high impedence peak means the driver isnt going to ring for long at all. A very smart guy I know wrote this, read it for more info on damping: http://www.audioasylum.com/forums/pi/messages/2062.html

This is why the morons who think that putting a woofer into a tiny box will make it sound "tight" and accurate for sound qualtiy are full of shit. In a smaller box, the resonance will shift up in frequency, and the peak will decrease. The cone will ring hard and long at these frequencies, yet they think this is good for sound quality... whatever.

Sensitivity at 1w/1m is refering to how much output the driver has with a 1w input, measureed one meter away from the cone, in a freespace environment (no boudry reienforcement, like walls). Sensitivity is kinda meaningless, because it will depend on the enclosure being used, frequency, and location of the enclosure. I actually think that they measure the sensitivity on a huge baffle, so the figures are inflated by 6dB, again, this depends on frequency, at high frequencies, the drop of 6dB will not happen, but that is a whole new story to tell..........

Le in mH is refering to the speakers inductance. Inductance is AC resistance basically, or the ratio of reactance to resistance. reactance is the amount of change you have in resistance with regards to frequency. In a speaker, the voicecoil is basically an inductor, so as frequency increases so does the resistance of the voice coil. This means that if your amp is rated at 100w into 4ohms, and the driver is 4ohms impedence, but say has a high inductance, when the frequency gets kinda high, like 2khz, the driver will not be able to be powered with 100w, because the resistance at this frequency will be much higher than 4ohms.

Originally posted by idontgiveashit sooooooooooo....anyone have an opinion based on the information now?

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Well, unfortunatly the T/S params don't always tell us how good quality the driver is. I would guess its fine, but how much did you pay for it? The linear excursion was only like 8mm one way i believe.

Well since the Xmax is only 8mm would that mean the motor is small on not that powerful.

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Linear excursion has nothing to do with magnetic field strength. For example, take one of the JBL pro drivers, with an xmax of 8mm. They have very high BL, yet their excursion is low. Their sensitivity however, is quite good.

Generally the drivers with more xmax tend to be less sensitive than low xmax drivers, meaning that for the same input, they have less output.

So that driver may have some advantages, however, for car subwoofers, that is QUITE low...